LAB Exam 1 Flashcards
What are the different methods for testing glucose?
- Oxidation Reduction
- Condensation reaction
- Enzymatic reactions (3 types)
What are the three glucose enzymatic reactions?
- Hexokinase (reference method)
– Glucose oxidase-colorimetric (Influenced by heparin)
– Glucose oxidase- polargraph (Influenced by heparin)
-Type of glucose Redox reaction that is not often used.
-Copper sulfate + Glucose –> Copper II oxide + Glucose-Na
-(In alkaline conditions & heat)
Benedicts- semi quantitative
-Glucose redox reaction
-Copper sulfate + Glucose —–> Copper II oxide + Glucose-Na
-Copper II oxide + phosphomolybdate —-> molybdenum blue
Folin Wu
Folin Wu reaction:
protein precipitation is….
Tungstic acid
Glucose redox reaction that uses Zinc sulfate and barium hydroxide
Somogyi Nelson
-Glucose redox reaction
-Ferric cyanide + Glucose —-> Ferrous cyanide (red color)
Automated Hagedorn Jensen
Condensation Reaction:
___________ condenses w/ Glucose in presence of Glacial acetic (hot)
producing blue green color (630 nm)
Ortho Toluidine
The condensation reaction for glucose can react with other aldoses like….
galactose and mannose
What kind of reactions are the most commonly used for testing glucose?
Enzymatic Reactions
Enzymatic Reaction:
Glucose + ATP ! G-6-P + ADP
G-6-P + NADP+ —> NADPH + 6-phosphogluconase
Hexokinase (reference method)
Enzymatic Reaction:
-Glucose + O2 —-> gluconic acid + H2O2
-H2O2 + Chromogenic peroxidase —-> Color + H20
Glucose Oxidase-colorimetric method (influenced by heparin)
-what we use in lab
Enzymatic Reaction:
Glucose + O2 —-> gluconic acid + H2O2
Glucose Oxidase- Polarography (influenced by heparin)
-needs electric current
What are the four lipid tests?
- TRIGLYCERIDES
- CHOLESTEROL
- HDL ASSAYS
- PHOSPHOLIPIDS
Why is TG testing done?
To calculate LDL using [LDL= total cholesterol-HDL-VLDL]
“ Friedewald equation”
-Assessment for CHD risk
-Determine whether increased TG are depressing HDL
High TG increases the risk of…
pancreatitis & numerous other clinical manifestations
How is TG and HDL related?
inversely related
What are the assays done for TG?
✓Hantzsch condensation
✓Sulfuric acid reaction
✓Pyruvate kinase/lactate dehydrogenase
✓Glycerol phosphate dehydrogenase/Diaphorase
What is the most frequently used “chemical” reaction for TG?
HANTZSCH CONDENSATION
Hantzsch condensation involves quantification of ________ using multiple steps
❖Organic extraction of TG
❖Chemical hydrolysis of TG to glycerol & FFA
❖Oxidation of glycerol to formaldehyde
glycerol
formaldehyde condenses with NH4+-Ac & acetylacetone to
form product which is measured between _____ and _____nm.
400 and 485nm
product measured is 3,5-DIACETYL-1,4-DIHYDROTOLUDINE
What are the first three steps of the Sulfuric acid reaction?
extraction, acidic/alkaline hydrolysis, & oxidation of glycerol
Sulfuric acid reaction:
utilizes chromotropic acid & sulfuric acid to produce a colored product upon reaction with formaldehyde
Eegriwe’s reaction
TRIGLYCERIDES —> GLYCEROL + 3 FATTY ACIDS (LIPASE)
GLYCEROL + ATP —> GLYCEROL-3-PHOSPHATE + ADP (GLYCEROL KINASE)
ADP + PEP —-> ATP + PYRUVATE (PYRUVATE KINASE)
PYRUVATE + NADH + H+ —-> LACTATE + NAD+ (LACTATE DEHYDROGENASE)
PYRUVATE KINASE/LACTATE DEHYDROGENASE
-frequently used assay
-enzymatic method for quantifying glycerol is multistep and measures NADH consumption